Conventional emission sources sometimes emit undesirable substances such as Ammonia (e.g., NH3), Hydrogen Chloride (e.g., HCl), Ammonium Chloride (e.g., NH4Cl), etc. The emission of these and other manufacturing byproducts at high concentrations into the atmosphere is often undesirable. Accordingly, it is a common requirement to have to continuously monitor a respective smoke stack for pollution to control emissions of certain types of pollution to be below threshold concentration levels.
Typically, continuous monitoring of an emission resource requires that a gas sample received from emission resource be conveyed to a monitoring system a short distance away. Conventional monitoring systems have the ability to monitor a concentration of different undesirable pollutants in the received gas sample.
It is often challenging to convey substances such as HCl, NH3, etc., in a sample line from a stack to a respective monitoring system because such substances tend to be sticky. That is, these particular pollutants readily stick to an inner surface of a conduit that conveys the respective gas sample from the stack to the monitoring system. In addition to being sticky, these substances are chemically reactive and can easily convert into undesirable byproducts such as ammonium chloride particles (NH4Cl), which also readily stick to inner walls of the sample line.
One outstanding issue with conventional monitoring systems is the positive zero offset caused by condensation of HCl and NH3 on inner walls of the conduit and the dissociation of NH4Cl particles after a long-term operation of the monitoring system. In other words, walls of a conduit conveying a respective gas sample from a source (such as a stack) to the monitoring system eventually can be contaminated or clogged with pollutants, impairing an ability of the monitoring system to accurately perform the function of monitoring pollutants.
In certain instances, such as when the sample line becomes clogged or lined with pollutants, the monitoring system may need to be shut down so that a technician can manually clean the sample line. In a worst scenario, when a conveyance line is so clogged, the technician will need to replace filters, probes, sample lines, etc., to restore a monitoring back to normal operation. As may be expected, physical replacement can be costly because a manufacturing plant may need to be shut down during replacement of components. The facility shut down can also cause the significant down time of emission monitoring system. As a result, the high payment for meeting emission compliance would be anticipated.